Methods of stimulating non-amyloidogenic processing of the amyloid precursor protein

Abstract

Stimulating non-amyloidogenic processing by the activation of cell surface serotonin receptors linked to phospholipase and protein kinase C is described. Activation of the cell surface serotonin receptors is accomplished by contacting the cell with an agent which is a serotonin agonist or which increases the intrasynaptic concentration of serotonin. Also described is the activation of cell surface serotonin receptors by dexnorfenfluramine. Agents which cause the activation of cell surface serotonin receptors can be administered to an individual to stimulate non-amyloidogenic processing in the brain of the individual, thereby inhibiting the deposition of amyloid in the brain of the individual.

What is claimed is: 
     
       1. A method of preventing, delaying or reducing the formation of amyloid plaques deposited in the brain of an individual in need thereof comprising administering to said individual a therapeutically effective amount of an agent selected from the group consisting of dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan. 
     
     
       2. A method of preventing, delaying or reducing the formation of amyloid plaques associated with a disease in which amyloid is deposited in the brain of an individual, by decreasing amyloidogenic APP processing in cells of the central nervous system of the individual, comprising administering to the individual in need thereof, a therapeutically effective dose of an agent selected from the group consisting of: dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan, wherein the agent is administered to the individual in such a manner that the agent contacts cells in the central nervous system. 
     
     
       3. A method of preventing, delaying or reducing the formation of amyloid plagues associated with a disease in which amyloid is deposited in the brain of an individual, comprising administering to the individual in need thereof, a therapeutically effective dose of an agent selected from the group consisting of: dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan, wherein the agent is administered to the individual in such a manner that the agent contacts cells in the brain which have the cell surface serotonin receptor. 
     
     
       4. A method of treating Alzheimer's disease in an individual in which amyloid is deposited in the brain, comprising administering to the individual a therapeutically effective dose of an agent selected from the group consisting of: dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan, in such a manner that the agent contacts cells in the brain which have the cell surface serotonin receptor. 
     
     
       5. The method of claim 4 additionally comprising administering to the individual a drug used in the treatment of Alzheimer's Disease. 
     
     
       6. A method of treating an individual who has Alzheimer's disease in which amyloid is deposited in the brain, comprising administering to the individual a therapeutically effective dose of dexnorfenfluramine. 
     
     
       7. The method of claim 6, additionally comprising administering to the individual a drug used in the treatment of Alzheimer's Disease. 
     
     
       8. The method of claim 1, said individual suffers from Alzheimer's disease. 
     
     
       9. The method of claim 2, wherein the disease in which amyloid is deposited in the brain is Alzheimer's disease. 
     
     
       10. The method of claim 3, wherein the disease in which amyloid is deposited in the brain is Alzheimer's disease. 
     
     
       11. A method of alleviating or delaying the progression of Alzheimer's disease in which amyloid is deposited in the brain of an individual in need thereof, comprising administering to the individual a therapeutically effective amount of an agent selected from the group consisting of: dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan.   
     
     
       12. The method of claim 11, additionally comprising administering to the individual a drug used in the treatment of Alzheimer's Disease. 
     
     
       13. A method of treating Alzheimer's disease in an individual in need thereof comprising administering to said individual a therapeutically effective amount of an agent selected from the group consisting of dexnorfenfluramine, dexfenfluramine, fenfluramine, fluoxetine, sertraline, paroxetine, fluvoxamine, tryptophan and 5-hydroxytryptophan. 
     
     
       14. The method according to claim 13, wherein said agent is dexnorfenfluramine. 
     
     
       15. The method according to claim 13, wherein said agent is dexfenfluramine. 
     
     
       16. The method according to claim 13, wherein said agent is fluoxetine. 
     
     
       17. The method according to claim 13, wherein said agent is sertraline. 
     
     
       18. The method according to claim 13, wherein said agent is paroxetine. 
     
     
       19. The method according to claim 13, wherein said agent is fluvoxamine. 
     
     
       20. The method according to claim 13, wherein said agent is tryptophan. 
     
     
       21. The method according to claim 13, wherein said agent is 5-hydroxytryptophan. 
     
     
       22. The method according to claim 1, wherein said agent is dexnorfenfluramine. 
     
     
       23. The method according to claim 1, wherein said agent is dexfenfluramine. 
     
     
       24. The method according to claim 1, wherein said agent is fluoxetine. 
     
     
       25. The method according to claim 1, wherein said agent is sertraline. 
     
     
       26. The method according to claim 1, wherein said agent is paroxetine. 
     
     
       27. The method according to claim 1, wherein said agent is fluvoxamine. 
     
     
       28. The method according to claim 1, wherein said agent is tryptophan. 
     
     
       29. The method according to claim 1, wherein said agent is 5-hydroxytryptophan.